An example of a technology regarding the OS configuration method in a processor system is disclosed in Japanese Patent Application Laid-Open Publication No. 11-149385 (Patent Document 1). This patent document 1 discloses the technology capable of simultaneously running a plurality of OSes, which comprises a step of separating a resource managed by a first OS from that managed by other OSes, a step of starting the other OSes, a step of switching the OS to be run, and a step of determining an OS which is to perform interrupt process based on an interrupt factor and starting an appropriate interrupt handler.